UNIT I INTRODUCTION AND PHYSICAL LAYER
Networks – Network Types – Protocol Layering – TCP/IP Protocol suite – OSI Model – Physical Layer: Performance – Transmission media – Switching – Circuit-switched Networks – Packet Switching
1. Exchange of data between two devices via some form of transmission medium such as a wire cable.
A. Data Communication
B. Network
Answer: A Data Communication
2. Information to be communicated which consist of text, numbers, pictures, sound or video combination.
A. Sender
B. Receiver
C. Message
Answer: C Message
3. Elapsed time between an inquiry and a response
A. Transit time
B. Response time
Answer: B Response Time
4. Provides a dedicated link between two devices
A. point-to-point connection
B. multipoint connection
Answer: A point-to-point connection
5. In bus topology, a ________________is a connection running between the device and the main cable.
A. Drop line
B. tap
Answer: A Drop line
6. The physical layer is concerned with ___________
A. bit-by-bit delivery
B. process to process delivery
C. application to application delivery
D. port to port delivery
Answer: A bit-by-bit delivery
7. The physical layer translates logical communication requests from the ______ into hardware specific operations.
A. network layer
B. trasnport layer
C. application layer
D. data link layer
Answer: D data link layer
8. Each upper level protocol is supported by the services provided by one or more lower level protocols.
A. hierarchical
B. Root structure
Answer: A hierarchical
9. In TCP/IP, The duty of the application, transport, and network layers is
A. hop-to-hop
B. end-to-end
Answer: B end-to-end
10. In TCP/IP, The duty of the data-link and physical layers is
A. hop-to-hop
B. end-to-end
Answer: A hop-to-hop
11. In TCP/IP , in the bottom two layers, the packet created by the host is changed only by
A. routers
B. link-layer switches
Answer: A routers
12. Responsible for taking the datagram and moving it across the link
A. Data-link Layer
B. Physical Layer
Answer: A Data-link Layer
13. Responsible for creating a connection between the source computer and the destination computer.
A. Data-link Layer
B. Physical Layer
C. Network layer
Answer: C Network layer
14. A protocol can decapsulate and deliver a packet to several next-higher layer protocols (one at a time).
A. Multiplexing
B. Demultiplexing
Answer: B Demultiplexing
15. A protocol at a layer can encapsulate a packet from several next-higher layer protocols (one at a time);
A. Multiplexing
B. Demultiplexing
Answer: A Multiplexing
16. It is a system in which a set of protocols that allows any two different systems to communicate regardless of their underlying architecture.
A. Open System
B. Closed System
Answer: A Open System
17. Four approaches that indicate network Performance
A. Bandwidth
B. Throughput
C. Latency (delay)
D. Jitter
E. All the above
Answer: E All the above
18. IS a measure of the number of bits that can pass through a network per second.
A. Throughput
B. Latency
Answer: A Throughput
19. Refers to the variation in the packet arrival time, that is an uneven delay in the delivery of audio or video packets.
Throughput
Latency
Jitter
Answer: C Jitter
20. Is the Physical path between source and destination that carry the information signals.
A. Transmission media
B. Transmission wavelength
Answer: A Transmission media
21. Is a cable that accepts and transports signals in the form of light.
A. Optical fiber
B. twisted-pair cable
Answer: A Optical fiber
22. Coaxial cables are categorized by their
A. Registered jack RJ ratings
B. Radio Government (RG) ratings
Answer: B Radio Government (RG) ratings
23. If the angle of incidence is ______to the critical angle, the light bends along the interface.
less than
equal
greater than
Answer: B equal
24. In this ______propagation, radio waves travel through the lowest portion of the atmosphere, hugging the earth.
A. sky
B. ground
C. line-of-sight
Answer: B ground
25. In _________ propagation, very high-frequency signals are transmitted in straight lines directly from antenna to antenna
A. sky
B. ground
C. line-of-sight
Answer: C line of sight
26. In _________ propagation, higher-frequency radio waves radiate upward into the ionosphere (the layer of atmosphere where particles exist as ions) where they are reflected back to earth.
A. sky
B. ground
C. line-of-sight
Answer: A sky
27. Radio waves travel in all directions from the source, so that the transmitter and receiver do not have to be carefully aligned physically
A. Uni directional
B. Omni directional
Answer: B Omni directional
28. When an antenna transmits microwaves, the sending and receiving antennas need to be aligned since microwaves are
A. Uni directional
B. Omni directional
Answer: A Uni directional
29. Signals can be used for short-range communication in a closed area using line-of-sight propagation
A. Infrared
B. Microwaves
C. Radiowaves
Answer: A Infrared
30. End to End circuit must be established in this phase
A. Setup phase
B. Data transfer phase
C. Tear down phase
Answer: A setup phase
31. When a frame arrives at a switch, it has a VCI; when it leaves, it has a different VCI.
A. True
B. False
Answer: A true